Research examining whether intentions to get a COVID-19 vaccine change over time is scarce. Moreover, the deep and pervasive history of medical racism in the U.S. has created a context in which some racial and ethnic groups exhibit greater levels of COVID-19 vaccine hesitancy; yet few researchers have attempted to determine whether these patterns persist with time. The purpose of this study was twofold: (a.) assess the role of time in COVID-19 vaccine intentions from April 2020 to January 2021, and (b.) examine whether race and ethnicity shape COVID-19 vaccine intention trajectories. Data were drawn from 9 waves of the Understanding America Study (n = 5023), a national probability panel study of U.S. adults. Multilevel logistic regression models were used to assess overall COVID-19 vaccine intention trajectories and trajectories by race and ethnicity. Results demonstrate intentions to get a COVID-19 vaccine significantly decreased from April 2020 to November 2020, but by January 2021, intentions to get a COVID-19 vaccine slightly increased. Findings also show trajectories significantly differed by racial and ethnic background. Asian/Pacific Islanders had the highest probability of likely getting a COVID-19 vaccine at baseline, followed by Whites and Latina/os. Black Americans exhibited the lowest probability of likely getting vaccinated, and, in most cases, the gap between Black Americans and other racial groups grew over time. Key findings from this study demonstrate that, among U.S. adults, time and race and ethnicity play significant roles in COVID-19 vaccine intentions. Understanding the role of time and race and racism in shaping COVID-19 vaccine intention trajectories can help government agencies and public health experts tasked with administrating vaccines better understand disparities in vaccine uptake.

Objective: Research examining how different dimensions of acculturative beliefs and behaviors influence the risk of biological dysregulation among Latina/os is limited. This study examined associations between three types of acculturation and allostatic load (i.e. a multisystem index of biological dysregulation) across gender and Latina/o ethnic groups. Multiplicative models were also included in order to determine whether immigrant generation moderates acculturation-allostatic load relationships. Design: Data were drawn from the Hispanic Community Health Study/ Study of Latina/os. The sample consisted of 11,841 Latina/os from five ethnic groups: Cuban, Puerto Rican, Dominican, Mexican, and South/Central American. The measure for allostatic load was derived from 15 biomarker and anthropometric measures that were designed to capture cardiometabolic risk, glucose metabolism, cardiopulmonary function, inflammation, and organ function. Acculturation measures, immigrant generation, gender, ethnic background, and other covariates were derived from self-reports. Survey corrected ordinary least squares regressions were used to assess relationships between different dimensions of acculturation and allostatic load. Results: Results demonstrate dimensions of acculturation play a significant role in the risk of biological dysregulation for Latina/os with divergent results across gender and ethnic background. Estimates from the multiplicative models show immigrant generation moderates acculturation-allostatic load relationships, and relationships are dependent on gender and ethnic background. Conclusion: The study contributes to the understanding of how different dimensions of acculturation, as well as other important structural determinants of health, influence the risk of biological dysregulation among Latina/os. Finding from this study can inform targeted strategies designed to reduce the physiological consequences of chronic stress among Latina/os.